code: def demo(self, x):
      x = self.conv(x)
      if self.has_bn:
          x = self.bn(x)
      if self.has_relu:
          x = self.relu(x)
      return x
  
imports: from __future__ import division
  from mxnet.gluon import nn
  from mxnet.context import cpu
  from mxnet.gluon.nn import HybridBlock
  from gluoncv.model_zoo.segbase import SegBaseModel
  from gluoncv.model_zoo.pspnet import _PSPHead
label_desc: Use image node_id 3 for calling the ConvBnRelu obj's underlying member method code with example usage: obj.demo(x) and returns: x